Lesson 1: Drafting Equipment – Tools And Materials
Drafting Machines
The drafting machines have replaced the T-Square and the triangles for drawing horizontal, vertical and inclined lines. A drafting machine consists of a head to which two scales are attached. (Fig.2 & 3)These scales (arms) of the drafting machine graduated like other architects scales are available in aluminum and plastic. The two scales are attached to the head of the drafting machine perpendicular to each other. The horizontal scale performs the function of a T-Scale or parallel slide in drawing horizontal lines. The vertical scale performs the function of a triangle in drawing vertical lines. The head of the drafting machine can be rotated so that either of the scales can be used to draw lines at any angle. The indexing thumb piece located on the protractor head is depressed to release the protractor head and required angle selected. Releasing the thumb piece will lock the protractor
Fig. 2 Elbow drafting machine
Fig.3Drafting machine
Parts of a Drafting Machine
A drafting machine combines the function of several tools. This combination allows drafting machines to implement several functions simultaneously on any one project. When these functions are broken down, you will see that drafting machines are quite complex and detailed.
Fig.4 Parts of a Drafting Machine
Protractor Head
The protractor head rotates to allow for angle selection. It contains a mechanism that allows it to be locked in place to secure desired angles.
Linkage
There are three types of linkage: pin joint, steel type and roller. While the steel type offers the ability to adjust tension in the bands, the roller type allows for the machines' use on a wider variety of projects.
Table Clamp
The clamp acts simply to secure the drafting machine to the table. Any adjustments to clearance and the protractor head position are made here as well.
Parallel Straightedges
The parallel straightedges maintain tension across the length of the tabletop by using a system of cords and pulleys. This allows an even edge at ends, as well as fluid and secure movement.
Steel Straightedges
Steel straightedges are the least popular of the straightedges. Although stronger and more durable, once they are bent or damaged, there is no fixing or repairing them, unlike their parallel counterparts.
T-Squares
The T-square--part head and part blade--allows for the drawing of straight lines and assists in the drawing of triangles. The head rests along the edge of the tabletop and glides back and forth, depending on where the blade is needed.
Participants